Enhance knowledge base functionality and integrate S3 storage support

- Add new models for `KnowledgeDocument` and `KnowledgeChunk` to manage document ingestion and chunking.
- Implement S3-compatible storage integration for knowledge documents, allowing for file uploads and retrieval.
- Introduce API endpoints for managing knowledge bases and documents, including creation, deletion, and searching.
- Update frontend components to support knowledge base configuration and document management, improving user interaction.
- Enhance backend services for knowledge processing and retrieval, ensuring robust handling of document statuses and errors.

backend/schemas.py

@@ -192,6 +192,35 @@ class KnowledgeBaseOut(KnowledgeBaseUpsert):
     updated_at: str | None = None
 
 
+class KnowledgeTextIn(CamelModel):
+    name: str = Field(min_length=1, max_length=255)
+    content: str = Field(min_length=1)
+
+
+class KnowledgeDocumentOut(CamelModel):
+    id: str
+    knowledge_base_id: str
+    name: str
+    source_type: str
+    mime_type: str
+    size_bytes: int
+    status: str
+    error_message: str = ""
+    chunk_count: int
+    created_at: str | None = None
+
+
+class KnowledgeSearchIn(CamelModel):
+    query: str = Field(min_length=1)
+    top_k: int = Field(default=5, ge=1, le=20)
+
+
+class KnowledgeChunkOut(CamelModel):
+    id: str
+    chunk_index: int
+    content: str
+
+
 # ---------- 接口定义驱动的统一模型资源 ----------
 class InterfaceDefinitionOut(CamelModel):
     interface_type: str